Community notes launched at the start of 2021. It predates the buyout by almost two years.
If what they said about their design is to be believed, political downvoting shouldn't heavily impact them. I wish it was easier to see pending notes on a post though.
Right, I think that's the parent's point: CN is a great design, dragged down by the fact that Elon heavily puts his thumb on the scale to make sure posts he likes spread far and wide and posts he dislikes get buried, irrespective of their truth content.
You can see them, it's just that finding the button to do so on a post is difficult. I think you need to navigate to the post from the notes section of the website.
If what they said about their design is to be believed, political downvoting shouldn't heavily impact them. I wish it was easier to see pending notes on a post though.